The Cause of Insulin Resistance

Mastering Diabetes Summit 2017

These are my notes from this interview. For more information visit the speakers web page.

Neal Barnard MD, F.A.C.C.
web page

The True Cause of Insulin Resistance and Type 2 Diabetes

Clinical researcher and author Dr. Barnard is one of America’s leading advocates for health, nutrition, and higher standards in research. As the principle investigator of several human clinical research trials, whose results are published in peer-reviewed medical and scientific journals, Dr. Barnard continues to examine key issues in health and nutrition. He is the founder and president of the non-profit organization Physicians Committee for Responsible Medicine. He is a NY Times best selling author and has written 17 books, including “Dr. Barnard’s Program for Reversing Diabetes,” in which he clearly lays out a program that is designed to target and reverse the root cause of diabetes using low-fat, plant based, whole-food nutrition. Link to his books on Amazon here.

Insulin resistance basically means you can’t get the fuel into your gas tank, your cells run on glucose and glucose comes from food. If a person has Type 2 Diabetes what’s happening is the glucose from food gets into the blood, but it cannot get into the cell where it can do some good. Most of the glucose from the food is supposed to go into the muscles, it powers your muscles, some of it goes to the brain and other parts. In insulin resistance, all it means is that the glucose is having trouble getting into the cell. The word insulin resistance comes from the fact that normally insulin, which is a hormone that comes from the pancreas through the blood, it’s like a key that opens up the cell to let the glucose inside. That’s the problem, if you have Type 2 Diabetes you’ve got insulin, it’s attaching to the cell normally but it’s not opening up the cell properly. The cell is resisting insulin’s efforts and the fuel can’t get into the cell where it belongs. One of the first symptoms is fatigue, you just don’t have any energy because you don’t have glucose inside your cells.

Insulin resistance is really caused by the buildup of fat inside the cells and this is something that nobody appreciated. At Yale University a number of years ago researchers used a technique call MR spectroscopy, the patient goes into the magnetic resonance machine, it’s like having an MRI for a knee injury. They use a special technique, what they’re looking at is not a broken ligament, they are looking inside the cells of the body. What they discovered is if you look inside the cells you see buildup of tiny fat particles, and this could be a person that doesn’t even have diabetes they could be 25 years old and really healthy. But you see the buildup of fat inside their cells and you know that’s a person who is headed for Type 2 Diabetes, it might be ten years from now. In other words the fat builds up inside the cell and it stops insulin from working, sugar is not really the issue. Don’t get me wrong I’m not saying a soda is health food, what I am saying is that the problem is the buildup of fat inside the cells. Especially animal fats, but I think you can overdo it with vegetable fats too.

Let’s say my cell is not responding to the insulin because I’ve been eating chicken wings and Velveta. The fat goes from the digestive tract into the blood and with surprisingly little change it ends up inside the cell. That makes the insulin not work very well anymore because, so I’ve got the buildup of fat inside the cell, the insulin key no longer works. The glucose which is relying on that key to get in the cell can’t get in anymore. So the blood sugar is building up because it can’t get in and the pancreas says, what’s all this sugar doing in the blood, and it starts making more and more insulin. Eventually it will get that sugar into the cell, but the buildup of insulin is a reaction to the fact that the glucose isn’t getting into the cell.

It’s true that most of the folks we see have Type 2 Diabetes are often well into adulthood, maybe older, often overweight. But, you can be young and you can be real thin and still have this disease because it’s not the belly fat that’s doing it. That’s in a way another side effect of the diet based on animal products and fatty foods. The problem is you might be very skinny, but, if you have fat inside the muscle cells, also inside the liver cells, that causes that insulin resistance. So it’s the intracellular fat, not the belly fat, not the fat between the cells, that may have other issues but the cause of insulin resistance is going on inside the cell.

Years ago in 2003 and 2004 we were recruiting for a research study where we wanted to use a plant based diet solely for weight loss to see what would occur. We brought in 64 women, they were all overweight, all after the age of menopause, they had done every diet known to humanity. We put them on a low fat plant based diet, they lost weight very effectively, roughly a pound a week. The question was why are you loosing weight, and the answer was really fascinating. The no brainer part of it was your suddenly eating beans, vegetables and fruits, and they have a lot of fiber, fiber has no calories so you fill up on high fiber foods. The brain thinks that you have eaten a lot, there’s not a lot of calories but there’s a lot of fiber I think that’s the biggest reason. However, when people came into the study many of them said, there’s something wrong with my metabolism, when I was 16 I could eat anything and now I just look at food and I gain weight. They were right, I know this because we put them on an exam table and we measured. We have a special canopy that goes over their head and shoulders and we’re measuring their oxygen intake and carbon dioxide output.

Pretty simple arithmetic will show you that calorie burn, their metabolism. It’s true, they were slow, we measured them right after they woke up and it was slow, we fed them breakfast and their metabolism starts to rise. That’s true for pretty much anybody because you’re absorbing nutrients, they’re getting into the cells, some is burning off as heat. Your metabolism rises for 3-5 hours after a meal. Then they go on a low fat plant based vegan diet for 14 weeks, they come back into the center. They lie down on the very same table, we put the same canopy over them, we feed them the same test meal. Their metabolism after the same meal was about 16% faster than before. When we poured over our statistics and looked at what predicted whether they lost 5 or 25 pounds. It turned out that this after meal metabolism was a big part of why they were loosing weight. Am I suggesting that if you’re eating a different way you can actually change how fast or slowly your body burns calories, yes, that’s exactly what I’m saying.

Researchers in Louisiana put them on a high fat diet as a test and within a matter of days you see the metabolisms are getting interfered with. What’s happening is fat gets into the cell, mitochondria, which are your little burners inside the cell that are going to burn up nutrients, start slowing down. Why, I just got all this fat in my cell I should be burning it up. Your body is programmed to store calories because your body evolved a long time ago back when starvation was a real thing, so when a big calorie influx happened your body stored it instead of burning it up. If you get a huge caloric intake of fats your mitochondria gets less active, stores the fat to insulate against the risk of starvation. Today every single meal can lead to obesity, high fat diets slow your metabolism and with a low fat diet your metabolism appears to rebound, this change will occur within 3-5 days. Weight starts coming off within a day or two, blood sugars start to come down within a day or two. We live in a country that eats a lot of fat, and we are not fat burning machines, two thirds of the country are overweight or obese. I think the paleo diet has crashed and burned in the scientific community, it still has a lot of romance imagining our forebears were effective hunters but it doesn’t have much to do with primate physiology.

Exercise in theory should help, you are burning calories that should burn fat. The reason I say in theory is the numbers are a little daunting. If I get on a treadmill and run as fast as I can for an entire mile and push the button that says how many calories did I burn, it says a hundred. Then I look at a DR. Pepper and it’s got 250 calories. Exercise you can do but your body is very efficient, if you burned off a pound or two every time you went for a run you couldn’t function that way. Human physiology is such that if you’re going to do athletic behaviors you have to do it without burning up a lot of body fat. Exercise is great, it has many benefits, but when you really want to tackle your weight it’s all in the imput side. The average person is eating a couple thousand calories a day and you don’t really burn off much with exercise. Exercise oxygenates your blood it’s good for the brain, there is evidence it helps with memory problems.

I’ve been taken with the reason why people eat junk, I’m talking cheese, meat, chocolate. It’s not that we were really hungry, it’s that we wanted to eat something. Well what are we doing, in the same way that alcohol, tobacco or illegal drugs work by releasing dopamine in the rewards centers of our brain, junk food does the same thing. There are things that release dopamine naturally, talking with friends, this is why support groups are so effective. Music and physical activity also releases dopamine, after a run you’re a little less likely to abuse yourself. I looked at cheese and why people say that’s the one thing they miss, one of the hormonal effects. First about a century ago Americans didn’t eat much cheese, the average was about 3.8 pounds a year and today it’s 35 pounds. It’s 70% fat on average, high in saturated fat, high in cholesterol, and sodium. Two ounces of potato chips, salty food, and 330 ml of sodium, velveta 800 ml, and we feed it to kids thinking it’s healthy.

The story about cholesterol is complicated because the government reversed itself. Now all those warnings are back in place and stronger than they were before, which is good. What happened was in 2015 the dietary committee looked at the data and cholesterol in foods doesn’t really effect your blood cholesterol. What they were responding to was the egg industry which has the highest food in cholesterol who convinced the committee to make this judgment. As soon as they did that we dug through the literature and here’s how it works. If I take a person who is not eating any cholesterol, not any eggs, and you give that person an egg every day their cholesterol level goes up noticeably. However, if I do a study and bring in people who are already eating a lot of cholesterol and you give that person another egg you don’t see much of any effect. It’s like if you have a person who is smoking a pack of cigarettes a day and you give them two more, you’re not going be statistically significant. That’s the kinds of studies the egg industry is doing and they are the prime funder of cholesterol research.

We brought this information to the USDA and it was changed to recommending as little cholesterol a day as possible. Industry is using science to keep people confused. You don’t need any because your body makes cholesterol, it’s important that your body make it. The liver makes most of it but the other cells make it, the reason is it goes into the cell membranes and keeps them flexible. You are a mobile, flexible human being keeping us that way. It’s also used as a raw material to make hormones like estrogens and testosterone. Progesterone is made out of cholesterol, vitamin D a key ingredient in making it. Your body makes a little of it for all those things and it makes all you need. When you eat animal products you’re getting their cholesterol added to your cholesterol, and it becomes too much. And about half of it ends up in the blood and some of the excess damages the arterial lining. The people who are on the paleo diet and their cholesterol level goes down it may be that it’s because what they are eating was better than what they were eating before.

Dairy is the number one bad source of fat in the diet.

A lot of men have it in their head that eating meat is macho but if you look at all the most muscular and macho animals on the planet they are all vegan. Eating a vegan diet your health soars and your cholesterol drops.

HDL cholesterol is the good cholesterol, high density lipoprotein, it’s called good because it’s removing cholesterol from the body. Up until fairly recently people would say, you do want a low total cholesterol, you want a low LDL, true enough, and they say you want a high HDL. Here’s where we get into trouble, first of all when people go on a plant based diet they don’t have much of any cholesterol in their body. Dean Ornish has a great explanation, he’ll say the HDL are garbage trucks but there isn’t enough LDL garbage to take away so your HDL are low. These people are very low risk for heart disease. Researchers have tested compounds that raise your HDL, pharmaceuticals, they found they don’t have any benefit. We knew that lowering LDL by diet or even pharmaceuticals would reduce your risk of heart disease. But the idea that HDL was good and help you when it’s been augmented pharmacologically, it hasn’t shown any benefit.

That’s where people are kind of scratching their heads. LDL is as bad as everybody thought it was but whether maintaining a high LDL really matters, the jury in my view is still out. For a healthy brain, again, your body makes all the cholesterol you need. You do need a certain amount of fat in the diet, if you send a leaf of spinach or some broccoli to the lab they will tell you it’s 7-8% fat, there are traces of fat in vegetables, beans, and fruits. Those are the traces that your body really needs, you then have enzymes, the alpha-linolenic acid that your body needs, and they elongate them to make the longer chain Omega 3s naturally. Except, if you eat a lot of other fats that interfere and get in the way, then that’s not good. You want to have a diet based on natural vegetables, fruits, grains, beans, that gives you traces of fat and there’s not a lot of competing fats to get in the way.

When you consume foods that are high in saturated fat, dairy is number one and meat is right there too. That saturated fat turns on the body’s mechanisms for manufacturing extra cholesterol. You didn’t eat this cholesterol your body made it in response to the fat your eating. There is something about a high saturated fat diet that starts to elevate the bad cholesterol levels in the blood. Animal products contain both saturated fat and dietary cholesterol so when you avoid animal products you avoid both. Unsaturated fat if you consume too much is not good either. And the man made trans fats act the same as saturated fat, with regards to their effect on cholesterol and should be avoided. When you take oils and you add hydrogen atoms to the fat molecule, it’s why it’s called hydrogenated, it turns this liquid oil into this waxy solid. Interesting enough that very same thing happens in a cows digestive tract, they create trans fats. In milk products you will see a little bit of what they call “natural” trans fats but it looks like their just as bad as the trans fats you get from a factory.

The typical lab slip says get your total cholesterol under 200, I would cross that out and probably put in 150. You will see some people who are way lower than that, a good total is 150 or less. For LDL roughly 100 or less, some say 90-70, triglycerides somewhere in the 100-150 range. Once you’re in those lower ranges I wouldn’t worry too much, and I wouldn’t get tested every two weeks, because your numbers are going to bounce around a lot. Depending on what your doing, what activity, what your eating and stress levels. If you look at people who have been on a plant based diet over the long term their triglycerides are low, if you look at them during the transition sometimes they bump up a little bit.

I did a study a number of years ago where I asked people to follow a vegan diet that was also low in fat, but, I added the glycemic index to it. What I was doing is instead of having white bread as an example I asked them to have rye or pumpernickel bread because those have less glycemic effect and don’t raise your blood sugar as much. Suddenly we saw everybody’s triglycerides go down. The higher glycemic foods are wheat bread, even if it’s whole grain, cold cereals are high, oatmeal and bran cereal is better, it’s lower GI. White potatoes tend to raise your blood sugar pretty rapidly, it doesn’t mean they’re unhealthy it means they release their glucose rather quickly. So you get a glycemic load that is more than the body can handle, so it’s probably converting that to triglyceride temporarily. On the other hand take a sweet potato your body digests it more slowly the glucose is released more gradually and you don’t seem to see that effect. Sugar of course tends to be high GI, fruit is sweet but it tends to be low GI. Just pick the low GI foods.

Final thought for diabetics, keep in mind where we want to go. We want to try to keep the fat out of your cells so your insulin can start working again. If your Type 1, I want to do the same thing because I want to stop the assault on the blood vessels, that’s the damage of Type 1. If I want to get the fat out of my cells what I want to do is eat foods that really don’t have much fat in them. That’s vegetables, fruits, whole grains and beans and all the healthy things they can turn into. Do take vitamin B12 as well, I think that’s important for everybody. Get some exercise when your having these foods, always have the healthiest one’s and not adding lots of junk to them. When you put it together it’s really pretty simple.

The person who is going to fail is the person who got that message that carbohydrates are somehow terrible and they’re avoiding the very food that’s going to give their cells the fuel that they need. When I say carbohydrates I’m not referring to sugar, what I’m saying is fruits, vegetables, whole grains and beans are the foods your body was designed for. Your body is designed to extract that carbohydrate, pull the glucose out of it and put it into your cells. The only reason the glucose can’t get into your cells is the cells have accumulated fat. You get the fat out of the diet, eat these healthy foods, and your cells are going to work better. If you have Type 1 the cells that make insulin are gone and you will need to continue a source of insulin. But, you don’t want any cholesterol in your diet because what hurts a person with Type 1 is blood vessel disease, so you don’t want any animal fat. You will discover you live a normal life if your eating a healthy diet. For some reason insulin requirements go way down.


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M. Scherker medical researcher